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Coastal circulation and transport of sediment derived from the Huanghe and Changjiang Rivers in the Bohai, Yellow, and East China Seas (BYECS) over the past 48 years (1958–2005) were simulated and analyzed using the Coupled Ocean–Atmosphere–Wave–Sediment Transport modeling system. Model skill assessments against in situ wave and hydrographical observations indicate the model simulation can reasonably well reproduce the hydrodynamic environment of the BYECS. Model-simulated regions of high fine sediment accumulation rate correlate well with the observed regions, which are known as “muddy patches.” Bottom stress analysis further indicates that the formation of muddy patches near river mouths is largely due to their proximity to the sediment source. Muddy patches formed in regions farther away from river mouths are results of local weak bottom stress and associated circulation pattern. Simulated seabed sediment distribution reveals that most of the Huanghe-derived sediment stays inside the Bohai Sea, whereas the Changjiang-derived sediment can spread into both the Yellow and East China Seas. Strong seasonal variations exist in the river-derived sediment transport with stronger (weaker) offshore sediment transport occurring in the winter (summer). [ABSTRACT FROM AUTHOR]

Distribution of suspended sediment in the Bohai Sea and its seasonal variability were investigated based on the datasets obtained from four cruises carried out in different seasons in 2010 and 2012. The results indicate that the spatial distribution of suspended sediment in the Bohai Sea was dominated by the river input and coastal resuspension that depends on the type of local surface sediment and hydrodynamics. The suspended sediment was mostly concentrated in the southern Bohai Sea particularly around the Yellow River Delta in the summer season as impacted by the river plume but confined within a very limited area near the river mouth, whereas in winter–spring seasons sediment concentration became much higher as a result of active coastal resuspension induced by energetic wave actions in the shallow water. High sediment concentration was found in Liaodong Bay in winter–spring seasons when dynamics become strong but decrease significantly in summer seasons. The sediment concentration in the southern Bohai Strait was much higher than that in the northern part, suggesting evident sediment export to the Yellow Sea particularly in the winter–spring seasons. Strong seasonal variability of suspended sediment distribution in the Bohai Sea was consistent with the monsoon activity and associated wave actions and coastal currents that are varying seasonally. The dominance of seasonal monsoon signal and associated wave dynamics make the subaqueous Yellow River delta to be a major sink for the terrestrial sediment in the summer seasons, but transiting to a primary source in winter–spring seasons for sediment redistribution in the Bohai Sea and sediment export to the Yellow Sea. The seasonal patterns of suspended sediment distribution in the Bohai Sea and the dominance of monsoon activities may provide a good reference to understanding the sediment transport in the China Shelf Seas where sediment resuspension and coastal circulation are evidently driven by monsoon. [ABSTRACT FROM AUTHOR]